The Animal Health Diagnostic Center at Cornell University now offers a non-invasive diagnostic test that readily distinguishes spayed from intact dogs and cats. This is an especially important consideration for shelters that require female pets to be spayed before adoption. Veterinary practices are often faced with uncertainties about the spay status of privately owned pets as well.

The test, known as anti-Müllerian hormone (AMH), looks for the presence or absence of AMH in a small serum sample. The ovaries are the sole source of AMH, and a negative test indicates that the ovaries have been removed. A positive test indicates that the animal is intact, or possibly that an ovarian remnant remains in an animal that was previously spayed. An animal with a piece of ovary that remains after the spay procedure may go into heat and display the undesirable behaviors that are associated with that condition. An AMH test can help determine if surgical exploration is warranted to find and remove an ovarian remnant.

“Before this test was developed, veterinarians had few good options to help them distinguish spayed from intact females,” said Dr. Ned Place, Director of the Endocrinology Laboratory at the Animal Health Diagnostic Center. “Surgical scars were once good indicators of spay, but now that dogs and cats are spayed at ever younger ages, the presence of scarring has become unreliable. Exploratory laparotomy is an option, but potentially unwarranted surgery is costly and poses medical risks. This diagnostic test, run on serum from a relatively small blood sample, is convenient, cost effective, and a benefit to dogs and cats, because AMH is found in the circulation whether or not an animal is in heat, and it requires no stimulatory hormones to elicit a response in intact females.”

For more information about the test, contact the Endocrinology Laboratory at the Animal Health Diagnostic Center at 607.253.3673.